全文获取类型
收费全文 | 195篇 |
免费 | 10篇 |
专业分类
林业 | 7篇 |
农学 | 5篇 |
36篇 | |
综合类 | 8篇 |
农作物 | 17篇 |
水产渔业 | 14篇 |
畜牧兽医 | 100篇 |
园艺 | 9篇 |
植物保护 | 9篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 8篇 |
2019年 | 2篇 |
2018年 | 14篇 |
2017年 | 6篇 |
2016年 | 5篇 |
2015年 | 11篇 |
2014年 | 3篇 |
2013年 | 13篇 |
2012年 | 16篇 |
2011年 | 11篇 |
2010年 | 9篇 |
2009年 | 12篇 |
2008年 | 13篇 |
2007年 | 15篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 9篇 |
2003年 | 7篇 |
2002年 | 3篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1996年 | 1篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有205条查询结果,搜索用时 156 毫秒
1.
本研究分为2个试验,试验I评定赖氨酸发酵蛋白粉在生长猪上的营养价值;试验2研究赖氨酸发酵蛋白粉等蛋白质替代豆粕对生长肥育猪生长、胴体性状和肉品质的影响。试验1:选用(25.0±1.1)妇杜×长×大三元杂交猪12头进行消化代谢试验,随机分为2组,每组6个重复,每个重复1头猪,分别饲喂无氮日粮和以赖氨酸发酵蛋白粉作为唯一蛋白质源的试验日粮,预试期4d,正试期4d。试验2:选用(41.7±3.9)kg杜×长×大三元杂交猪100头进行饲养试验,随机分为4组,每组5个重复,每个重复5头猪。I组为对照组,饲喂基础日粮;Ⅱ、Ⅲ和Ⅳ组分别为饲喂赖氨酸发酵蛋白粉等蛋白质替代10%、25%、50%豆粕的试验日粮,体重达100kg左右结束。消化代谢试验结果表明:赖氨酸发酵蛋白粉消化能为12.85MJ·kg^-1,代谢能为11.80MJ·kg^-1。总氨基酸含量为47.38%,总氨基酸的回肠表观消化率、真消化率分别为66.95%和70.52%,赖氨酸和蛋氨酸的回肠表现消化率、真消化率分别为72.00%、75.14%和59.37%、64.52%。试验结果表明:与对照组相比,在生长期和全期,Ⅳ组平均日增重显著降低(P〈0.05),料重比显著升高(P〈0.05);在肥育期,Ⅳ组平均日采食量显著增加(P〈0.05),料重比显著升高(P〈0.05),生长期和肥育期,Ⅳ组氮消化率、氮生物学效价显著降低(P〈0.05)。Ⅳ组背膘厚显著增加(P〈0.05),眼肌面积和肌肉保水能力显著降低(P〈0.05)。由此得出,与豆粕相比,赖氨酸发酵蛋白粉的粗蛋白质和脂肪含量较高,非蛋白氮比例大,氨基酸消化率低。蛋白质替代10%和25%豆粕对40-100kg的生长肥育猪生产性能、胴体性状和肉品质均无影响,可作为饲粮中的新型蛋白质原料。 相似文献
2.
In this study, the prediction of pine mistletoe distribution in Scots pine ecosystems was explored using remote sensing variables to compare the multilayer perceptron (MLP) artificial neural network (ANN) and logistic regression (LR) model performances. For this purpose, 109 sample plots were distinguished in pure Scots pine forests (natural) in the Eastern Black Sea Region of Turkey. Distinguishing mistletoe-infected stands (69) and uninfected stands (40) was performed with field observations. The variables acquired from Landsat 8 (Level 1) images were used as independent variables for independent-sample t-test, MLP ANN and LR models. Remote sensing variables indicated that mistletoe-infected stands were in drier areas with a lower vegetation-leaf area index. Based on the performance results of both models, the sensitivity (SEN), specificity (SPE), positive predictive value (PPV), negative predictive value (NPV) and accuracy of the MLP ANN model were superior to those of the LR model. The prediction percentages (SEN, SPE, PPV and NPV) of mistletoe-infected stands were better than the prediction percentages of uninfected stands. The prediction accuracies of LR and MLP ANN models were 74.3% and 89.6%, respectively. However, all remote sensing variables were included in the prediction equation of the MLP ANN model, while the thermal infrared 1 (TIRS1) variable was included in the LR model. In the MLP ANN model, the TIRS1 variable also had the highest normalized importance (100%). The area under the curve (AUC) value for identifying the mistletoe-infected stands of Scots pine forests used by the MLP ANN model (0.892 ± 0.034) was higher than in the LR model (0.838 ± 0.039), explaining the more accurate predictions obtained from the MLP ANN model. The MLP ANN model showed much better performance than the LR model. The results of this study are expected to make important contributions to the identification of potential mistletoe-infected areas. 相似文献
3.
Increasing irrigation costs and declining water availability compel producers to adapt irrigation strategies for maximum crop yield and water use efficiency. A field trial was conducted to observe the effects of various drip irrigation ratios (IR-0, IR-25, IR-50, IR-75 and IR-100) on water use efficiency (WUE), the irrigation water use efficiency (IWUE), lint yield, yield components and fibre quality at two upland cotton varieties during 2004 and 2005. WUE was found to increase from 0.62 to 0.71 kg m−3 as the irrigation water applied was reduced from 100 % to 75 % of soil water depletion. Deficit irrigation of cotton with drip irrigation at 75 % treatment level (IR-75) did not decrease seed cotton yield and yield components during 2 years, with the exception of the number of bolls in 2005. Among fibre quality parameters, no significant differences in fibre length, fineness, uniformity index and elongation were detected between the 100 % and 75 % irrigation levels in 2005. The results revealed that irrigation of cotton with a drip irrigation method at 75 % level had significant benefits in terms of saved irrigation water without reducing yield, and high WUE indicated a definitive advantage of employing deficit irrigation under limited water supply conditions. 相似文献
4.
Burcu Sancar Beşen Onur Balcı Cem Güneşoğlu Mehmet Orhan E. İnci Somuncuoğlu İ. İrem Tatlı 《Fibers and Polymers》2017,18(6):1079-1090
In this paper, it was aimed to obtain disposable medical textiles having antibacterial and wound healing properties, as well as biological adaption. For this purpose, the St. John’s Wort oil and flax seed oil were ozonated, and the oils were capsulated with arabic gum. The produced ozonated oils were characterized through FTIR and TGA analyses, as well as the properties of antibacterial, wound healing, and biological adaption were investigated. The produced microcapsules were examined via optical microscope and FTIR. The characterized microcapsules of the ozonated oils were applied to the textiles with padding method. After the applications, the fabrics were researched with SEM and FTIR analyses; in addition the antibacterial and wound healing properties and biological adaption of the textiles were also investigated. The results showed that the St. John’s Wort oil and flax seed oil were successfully ozonated and microcapsulated. The microcapsules of the oils could be applied to the fabric samples with the determined application recipe. The ozonated oils and the fabric samples applied microcapsules of the ozonated oils gained high antibacterial and wound healing property. In addition, the fabric samples were produced as having biological adaptation. 相似文献
5.
6.
Yilmaz A Kaleta EF 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(9):461-465
Various materials with rough surfaces were tested to determine their suitability for virus carrier tests designed to evaluate virucidal activity of chemical disinfectants. A non-enveloped RNA virus, bovine enterovirus type 1, strain LCR 4 [entero cytopathogenic bovine orphan virus (ECBO)] and an enveloped RNA virus, paramyxovirus type 1 [Newcastle disease virus (NDV), strain Montana] served as test viruses. Experiments with ECBO virus were carried out in four sets, and those with NDV in three sets. In the first set we used poplar wood, frosted glass slides and Sartorius membrane filters. The second set comprised of poplar wood, frosted glass slides, polyamide filters, and cellulose nitrate filters and, in the third set, glass fibre filters and glass fibre pre-filters were added. The fourth test included poplar wood, frosted glass slides, and polyethersulphone ultra filters. Because of their extremely low levels of virus recovery, glass, polyamide, cellulose nitrate and glass fibre filter, glass fibre pre-filter, and polyethersulphone ultra filters are not suitable for sufficient recovery of ECBO virus. Only poplar wood carriers allowed sufficient recovery rates of ECBO virus. In the first and second set of tests, NDV could be sufficiently recovered from poplar wood, glass slides, and polyamide filter. In the third set, the virus recovery from polyamide filter was very low. Poplar wood carrier is recommended as a reliable carrier for the tests with both viruses, but methods for virus recovery must be improved, e.g. by more vigorous and longer shaking or optimizing the ultrasonic treatment. 相似文献
7.
1. This study was conducted to examine some egg characteristics and determine the effects of eggshell thickness and eggshell porosity on water loss and hatchability of eggs in ostriches. 2. Shell thickness did not correlate significantly with hatchability. However, eggs of low shell thickness lost more mass (13.03%) than those with intermediate (11.22%) and high (10.36%) shell thickness. Mass loss during incubation was higher in hatched (11.98%) than unhatched eggs (11.09%). Shell thickness was negatively correlated to egg mass loss (r = -0.65). 3. The pore density was correlated with hatchability. Hatchability was 50% lower in eggs with low pore densities (40.93%) than with high densities (80.94%). Pore density was positively correlated with egg mass loss (r = 0.63). Incubation mass losses of hatched and unhatched eggs were not significantly different. 4. Mean eggshell water vapour conductance (G) value and shell conductance constant (k) were 87.77 +/- 4.21 mg H2O/d/Torr and 2.44 respectively (n = 15). 5. Because of eggshell functional properties and resulting low egg mass loss hatchability is low when ostrich eggs are artificially incubated. The mass of eggs used in the experiment was relatively high and their eggshell water vapour conductance was low. As a result, egg incubation mass loss was lower than it should be. It is concluded that incubator humidity should be low (25%) to allow enough mass loss during incubation from the eggs. 相似文献
8.
The incidence, severity and distribution of six viruses infecting capsicum were determined in the main growing areas of Turkey during the 2004 growing season. The surveys covered 50 randomly selected capsicum fields from four different areas in south-east Anatolia and the eastern Mediterranean region. 515 samples were individually collected and tested by DAS-ELISA for Cucumber mosaic cucumovirus (CMV), Alfalfa mosaic alfamovirus (AMV), Potato X potexvirus (PVX), Potato Y potyvirus (PVY), Pepper mild mottle tobamovirus (PMMoV) and Tobacco etch potyvirus (TEV). 64.8% of ELISA-tested capsicum samples (334 out of 515) were infected by one (41.7%) or more (23.1%) viruses. PVY was the most widespread (26.4%), followed by PVX (25.8%), AMV (25.2%), TEV (23%), PMMoV (9.1%) and CMV (8.3%). Surprisingly high AMV infection was found in three areas (Kahramanmaraş, Şanlıurfa and Gaziantep) where AMV is reported for the first time in this study. However, AMV was not detected in Hatay. PMMoV is another new virus, in all the tested areas. 相似文献
9.
Onur Yilmaz Mehmet Kizilaslan Yunus Arzik Sedat Behrem Nezih Ata Orhan Karaca Cengiz Elmaci Ibrahim Cemal 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2022,139(1):26-39
Sheep are considered as a major contributor of global food security. Moreover, sheep preweaning growth traits as well as in vivo carcass composition traits such as ultrasonic measurements of Longissimus dorsi muscle depth (UMD) and back-fat thickness (UFD) are crucially important indicators of meat yield and hot carcass composition. Despite their relative importance for productivity and profitability of a sheep production system, detected QTL for these traits are quite scarce. Therefore, we implemented GWAS for these traits using animal mixed model-based association approach provided by GenABEL in Esme sheep. Three genome-wide and 14 individual chromosome-wide associated SNPs were discovered. As a result, ESRP1, LOC105613082, ZNF641, DUSP5, TEAD1, SMOX, PTPRT, RALYL, POM121C, PHIP, LOC101106051, ZIM3, PEG3, TRPC7, FBXL4, LOC105610397, LOC105616489 and DNAAF2 were suggested as candidates. Some of the discovered genes and involved pathways were already annotated to contribute growth and development in various species including human, mice and cattle. All in all, the results of this study are expected to strongly contribute to shed a light on the underlying molecular mechanisms behind growth and carcass composition traits, with potential implications on studies aiming faster genetic improvement, targeted low-resolution SNP panel designs and genome-editing studies. 相似文献
10.